1. Field of the Invention
The present invention relates to tools for sanding a surface and, more specifically, to a sanding sponge constructed of a cellular foam material.
2. Description of Related Art
Abrasive sanding tools are used in a wide variety of applications which require smoothing, cleaning, feathering, or otherwise finishing a surface. Some applications, such as sanding corners and angles of finished dry wall, require hand sanding where a user will grasp a coated abrasive sheet in their hand and apply it directly to the surface being treated. This process is often ineffective because irregular pressure, such as caused by fingers against the back side of the abrasive sheet in use, produces an irregular abraded surface, or because the surface to be treated is difficult or impossible to reach directly by hand.
In order to overcome this inefficiency, several tools which assist in the holding of an abrasive surface have been disclosed in the related art. These have included hand-held foam blocks having abrasive surfaces permanently or removably attached thereto and handle attached rigid blocks having an abrasive surface fixedly or removably attached thereto.
U.S. Pat. No. 5,054,248, issued Oct. 8, 1991 to Donald R. Thayer, discloses a hand-held sanding sponge molded from a flexible cellular foam into a block having an easily gripped handle on its top surface and an abrasive layer removably attached to its bottom surface. One edge of the bottom surface is acutely angled while the opposed edge is curved to allow the sanding sponge to be used on a variety of surfaces including corners and curved surfaces.
U.S. Pat. No. 5,131,193, issued Jul. 21, 1992 to Michael J. Demers, discloses a hand-held sanding tool adapted for abrading a surface having a specific contour. The tool has an upper portion forming an easily gripped handle and a lower portion having an abrasive surface with a predetermined profiled contour matching the configuration of a groove wall on an automobile part.
U.S. Pat. No. 3,998,012, issued Dec. 21, 1976 to Reuben Ness, discloses a sanding sponge in the form of a cellular plastic cylinder having a layer of abrasive material removably secured to its bottom end with an adhesive substance. The bottom end of the sanding sponge may have a variety of curved or angled contours and the top end of the sponge may have a layer of fibrous material adhered thereto to act as a cushion for the users hand and to be used to remove dust from the surface being treated.
U.S. Pat. No. 4,202,139, issued May 13, 1980 to In S. Hong and Glen E. Roelofs, discloses a hand-held sanding tool comprising a pad having a bottom surface adapted to have an adhesive coated abrasive sheet attached thereto and a top surface having a handle adapted to be wrapped around one or more of a users fingers to hold the pad in place on the users hand. The sanding tool of Hong et al. is intended to minimize the user's discomfort while sanding.
U.S. Pat. No. 4,825,597, issued May 2, 1989 to William Matechuk, discloses a handle mounted sanding tool adapted for sanding corner joints in dry wall construction. The tool has a resilient foam block which has two abrasive faces adapted to fit the contour of a corner and which is mounted on a pole-attached carrier that properly distributes the force exerted on the handle to the faces of the foam block.
U.S. Pat. Nos. 2,817,931, issued Dec. 31, 1957 to Burdette C. Houser, and 3,279,130, issued Oct. 18, 1966 to Arthur E. Nelson, also disclose handle mounted sanding tools adapted for sanding corner joints. Both tools have carriers with two faces joined at an angle that are adapted to have sandpaper wrapped therearound and secured in place.
U.S. Pat. No. 4,774,789, issued Oct. 4, 1988 to Jerome L. Amalfi, discloses a hand-held sanding tool adapted for sanding an external corner. The sanding tool of Amalfi has two opposed plates with abrasive surfaces joined at a right angle which are reciprocated by a motor in the small handle extending rearwardly from the opposed plates.
U.S. Pat. No. 4,885,876, issued Dec. 12, 1989 to David R. Henke, discloses a sanding tool for sanding a flat surface which has a hand grip which is interchangeable with a pole grip. The tool is adapted to have sandpaper wrapped around a base member and secured in place by attaching one of the grips to the top of the base member.
U.S. Pat. No. 2,523,884 issued Sep. 26, 1950 to H. R. Swenson discloses a sander-scraper combination having a sander block having a rectangular shape. Swiss Patent 345,435 published May, 1960 discloses a sanding block mounted to a pole sander, the block being rectangular with radially shaped ends. United Kingdom Patent Number 2,065,512 issued Jul. 1, 1981, discloses a hand tool with a handle and a blade, the blade being essentially a sanding block having sand paper wrapped around both faces and retained by clips, but no pad, the blade having a variety of shapes including rectangular and wedge shapes.
European Patent Number 315,287 published Oct. 5, 1989 discloses a hand sander including a plate or block having four symmetrically arranged holes, the sand paper extending through the holes and being clamped by tongues. United Kingdom Patent Number 2,244,945 issued Dec. 18, 1991 discloses a hand held sanding block having a flexible band of sand paper fitting snugly around the circumference of the block.
None of the prior art, however, discloses a sanding sponge made of a flexible foam material which has a nonabrasive surface, adapted alternatively to be held by the user's fingertips or to be placed on the end of a pole sander, with two acutely angled edges on opposed sides of its primary abrasive surface.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.